armitage



March 3, 1964 H. J. ARMITAGE 1 3 BENDING APPARATUS 3 Sheets-Sheet 2 Filed Jan. 9, 1961 March 3, 1964 H. J. ARMITAGE 3,123,124

BENDING APPARATUS Filed Jan. 9, 1961 3 Sheets-Sheet 3 Fig. 5.

' Fig.6.

SKID

ASSEMBLY United States Patent 3,123,124 BENDING APPARATUS Harry J. Armitage, Monroeville, Pa. (Box 278, Murrysville, Pa.) Filed Jan. 9, 1961, Ser. No. 81,392 13 Claims. (Cl. 15316) This invention relates to the material forming art and has particular relationship to bending apparatus particularly for bending force resistant materials of substantial thickness.

In the making of power transformers (for example 15,000 kva.), it is necessary that the terminals of these transformers be bent. These terminals are copper or aluminum bands or strips of substantial width and thickness and they are connected to the windings. Typically the terminals may have a thickness of .125 inch and a width of .450 inch. A number of terminals extend from a transformer and are differently arranged for different transformers.

Prior to this invention the terminals were bent, one at a time, by an operator who used a plier-like tool and produced the bend by applying his strength to the tool. This operation is highly time consuming and costly and it is an object of this invention to reduce the labor cost of bending material such as transformer terminals.

Material bending machines in accordance with the teachings of the prior art are not applicable to the bending of transformer terminals. Such prior art machines are provided with jig facilities for holding and bending stock such as pipes, tubes, sheets, or rods but they are incapable of accommodating a power transformer so that its terminals may be bent. In addition these machines are highly complex including numerous drives of different types.

It is then another object of this invention to provide bending apparatus of simple structure particularly suitable for bending power transformer terminals at a relatively low labor cost.

This invention in its most rudimentary aspects arises from the realization that for the economic bending of the transformer terminals power and not muscle operated apparatus is essential but it is necessary to bring the bending apparatus to the transformer rather than taking the transformer to the bending apparatus, and it is a further object of this invention to provide such portable power operated bending apparatus.

An incidental object of this invention is to provide a novel drive particularly suitable for portable bending apparatus.

In accordance with this invention in its specific aspects portable power operated material bending apparatus is provided in which the operating power which is necessarily high is provided by a unitary drive. Preferably this drive is of the fluid impelled type. Such a drive includes a cylinder in which a piston is actuatable by fluid pressure.

The bending apparatus in accordance with the specific aspects of this invention includes work holding means and work bending means. Specifically this work means may include an anvil, a holding die, or clamping assembly, and a bending die or skid assembly. The unitary drive is connected to the holding means and to the bending means to actuate the holding means into holding engagement with the work and the bending means into bending engagement with the work. In accordance with an important specific aspect of this invention the cylinder of the drive is mounted mechanically floating so that when fluid pressure is applied both the cylinder and the .piston move relative to each other. The cylinder is connected to actuate one of the work means and the piston the other work means. In the interest of simplicity and 3,123,124 Patented Mar. 3, 1964 "ice economy in construction, the cylinder is connected in an embodiment of this invention to actuate the holding die or clamping assembly and the piston, the bending die or skid assembly.

In the practice of this invention a plurality of the terminals are bent simultaneously. The terminals may conveniently be mounted for bending in the apparatus in several ways. To describe the different mountings it is de sirable to define the different sides of the band which constitutes a terminal. Such a band is in its unbent condition essentially a long, thin rectangular parallelepiped. The longest cross-sectional dimension of this strip may be called the width and the shortest cross-sectional dimension the thickness. The third dimension is the length. The plane defined by the length and the width is called the elongated surface of the terminal and the plane defined by the length and the thickness is called the edge of the terminal.

Depending on their positions on the transformer the simultaneous bending of the terminals may be effected with the terminals side-by-side; that is, with their elongated surfaces coplanar or with the terminals superimposed; that is, with their elongated surfaces stacked and with their edges coplanar. In accordance with an aspect of this invention, the work holding and work bending means are so made as to accommodate pluralities of terminals of different dimensions in the above described different positions. Specifically the anvil is provided with a flange and the work is positioned between the anvil flange and a flange on a cap which may be set at different distances from the anvil flange. The cap may have a wide flange for positioning terminals with their elongated surfaces coplanar and a narrow flange for positioning terminals with their elongated surfaces superimposed.

The power supplied by the drive must be adequate to effect the secure holding and the bending of the material. It is an important specific feature of this invention that the power is supplied by a fluid operated drive. With such a drive adequate power is readily available; it is only necessary to impress adequate fluid pressure between the piston and cylinder.

In accordance with the broader aspects of this invention the drive may be an electric motor properly geared to the work holding and bending means. One of the desirable features of this invention is the mounting of the drive in such a way that the casing for the drive serves as a handle by means of which the operator may hold or mount this bending apparatus near the transformer. In accordance with the broader aspects of this invention, this feature may be adapted to portable apparatus in which the drive includes separate cylinders or motors for bending and holding.

The more important novel features considered characteristic of this invention are discussed above. For a better understanding of this invention both as to its organization and as to its method of operation, and for a realization of additional objects and advantages thereof, the following detailed description of an embodiment of this invention taken in connection with the accompanying drawings is presented. In the drawings:

FIGURE 1 is a view in top elevation of a preferred embodiment of this invention showing the work in clamped position with the bending die, or Skid Assembly, in position to start the bending;

FIG. 2 is a view in top elevation of the embodiment shown in FIG. 1 in fully open or release position with the Clamping and Skid Assemblies removed;

FIG. 3 is a view in end elevation of the embodiment as shown in FIG. 2;

FIG. 4 is a View in section taken along line IV-IV of FIG. 2 but with the Clamping Assembly mounted;

FIG. 5 is a view in section taken along line V-V of FIG. 2 but with the Clamping Assembly present;

FIG. 6 is a view in section taken along line VI-VI of FIG. 2 but with the Skid Assembly present; and

FIG. 7 is a view in section taken along line VIIVII of FIG. 2 but with the Skid Assembly present.

The apparatus in accordance with this invention includes a Drive, an Anvil, a Clamping Assembly, a Skid Assembly, and a Connecting Assembly, between the Drive, Clamping Assembly and Skid Assembly. This apparatus is powered by fluid pressure which may be derived through valves (not shown) from compressed air or a liquid but must be adequate for bending the relatively thick metals to be processed. The dimensions of the apparatus is such that it is readily portable. The parts must have suificient strength to withstand the direct and reactive pressures to which they are subject.

The Drive includes a sleeve 11 within which a cylinder 13 is slidably mounted. The cylinder 13 thus floats mechanically within the sleeve 11. At one end the sleeve 11 is cut away around a portion of its periphery leaving a projecting portion 15 (FIG. 4).

The cylinder 13 includes a cylindrical shell 17 having plugs 19 and 21 screwed into its ends. The screw junction on each side is substantially fluid tight. The plug 19 is reentrant internally and has a central threaded opening which communicates with the inside of the cylinder through a central hole 23. A fitting 25 for supplying fluid is screwed into the opening. The other plug 21 has a central opening provided with a bearing sleeve 27 (FIG.

'4) along a portion of its length and including an O-ring 29 intermediate the remaining portion. A rod 31 connected to a piston 33 is slidable on the sleeve 27. The plug 21 also includes a threaded opening on one side of the center communicating with the interior of the piston 13 through a hole 35 and another threaded opening on the other side of the center extending partly through the plug. Another fitting 37 for supplying fluid is screwed into the former opening and a rod 39 connected to the Clamping Assembly is screwed into the latter opening.

The piston 33 is externally of circularly cylindrical shape and is provided with O-rings 41 intermediate its ends so that it is sealed fluid tight against the surface of the cylinder 13. On the side subject to pressure from the fluid entering through fitting 25, the piston 33 has a generally trapezoidal opening 43 which communicates with a hole 45 in the rod 31. Because of the supply of fluid both through fitting 25 and through fitting 37, the pressure on piston 33 is double acting.

The Anvil includes a block 47 from which a stem 49 (FIG. 4) extends. The stem 49 is in the form of a section of a circular cylinder having an external radius such that it seats in the upper portion of sleeve 11 (FIG. 4). The stem 49 is bolted to the sleeve 11. The block 47 has straight portions 51 and 53 at an angle somewhat greater than 90 joined by a curvilinear portion 55. The work W is clamped against the straight portion 51 by the Clamping Assembly and is bent about the curvilinear portion 55 by the Skid Assembly (FIG. 1). A flange 57 for positioning the Work extends around the periphery of the block 47.

The block 47 has a hole substantially at the center of the curvilinear portion 55. A bolt 59 (FIG. 1) extends through this hole and is secured to the block 47. This bolt 59 has an unthreaded stub portion 61 which serves as a pivot for the part of the Connecting Assembly cooperative with the Skid Assembly. The block 47 has a surface recess 62 in which a key screw 63 is screwed. The key tip 65 of screw 63 engages a slot 67 in rod 39 permitting the rod 39 to move in a direction parallel to the direction of movement of the piston rod 31 but preventing the rod 39 from turning.

The Clamping Assembly includes a block or strap 69 in the form of a rectangular parallelepiped with one of the smaller area faces cylindrical (FIG. 2). A pin 71 threaded at its end extends from block' 69. The rod 39 is secured transversely to the block 69 by a pin 73 and the block 61 is thus movable with the cylinder 13. The

block 69 has lateral openings in which pins 75 are inserted. The pins 75 extend from the base of the block 69 above its opposite surface.

A support 77 for a cap 78 is removably mounted on tions; one position as shown in FIG. 4 and the other position with the pin 71 engaging opening 81. In the latter position, the cap 78 is nearer the face 51 of the Anvil than in the former position. The support 77 has openings 33 (FIG. 5), the axes of which are in a plane at right angles to the plane of the axes of openings 79 and 81. These openings 83 have smaller diameter portions adapted to engage the pins 75. The smaller diameter portions merge into larger diameter portions in which springs 85 are inserted. The springs 85 urge the cap 78 outwardly along the pin 71 when the cap is disposed on the pin 71. The cap may be locked in any position by nuts 87.

The cap 78 is of generally channel form but has a wide flange 89 and a narrow flange 91. The web of the cap is provided with an opening centrally disposed with respect to the channel as a whole. (See 'FIG. 1.) The opening is dimensioned to be removably engaged by pin 71. With the cap holder 77 on pin 71, the cap 78 is positioned on the cap holder. The cap 78 is set so that the pin 71 passes through the opening 79 or the opening 81. If the pin 71 passes through opening 79, the flange 89 is nearest the block 47 of the Anvil and if the pin passes through opening 81, the flange 91 is nearest the block 47. The nuts 87 are adjusted on pin 71 to correspond to the dimensions of the work W. In each case the height of the flange 89 or 91 above the flange 57 of the Anvil is set so that the flange '89 or 91 just clears the outer surface of the work W.

The Skid Assembly is pivotally. supported on a strap or block 95 (FIGS. 2 and 4) which is suspended piv-' otally on a pin 97 from pivot arm 99. The pivot arm 99 constitutes a part of the Connecting Assembly and is pivotally mounted on the portion 61 of pivot bolt 59 (FIG. 7). The strap 95 is urged towards the tip of arm 99 by a spring 100 (FIGS. 2 and 4).

The Skid Assembly includes a skid pin or skid shaft 101 (FIG. 7) having a head 103 and threaded at its end. The strap 95 has a hole near its end remote from the pivot pin 97 in which it engages the shaft 101; the strap 95 is engaged between a washer 105 on head -103 and a shoulder on shaft 101. The shaft 101 has another extended shoulder 107 on which a cap-supporting block 109 (FIGS. 6 and 7) is mounted. The block 109 has holes 111 with internal shoulders symmetrically disposed with respect to its axis 110 perpendicular to shoulder 107. In each of these holes 111 there is a spring 113. The block 109 also has a hole 115, the axis of which is displaced from the axis 110; the axis of this hole lies in a plane at right angles to the plane defined by the axis 110 and the axes of holes 111. The shaft 101 engages the support 109 in this off center hole 115.

The cap 117 of the Skid Assembly is of generally chanrligll form having a wide flange 119 and a narrow flange through which the shaft 101 passes. When the cap 117 is mounted, it is urged away from support 109 by springs 113. The cap may be secured in any position to accommodate the dimensions and arrangement of the work W by nuts 123. 7

The cap 117 and its support 109 may be set on shaft 101 with wide flange 119 nearest the block 47 (as in FIG. 7) for the bending of strips W disposed on flange 57 side by side or they may be set with flange 121 nearest block 47 for the bending of strips which are superimposed.

In either case the cap 117 is positioned so that flange 119 The cap 117 has a central opening in its web.

or 121 just clears the work. The cap 117 skids along the work W during the bending operation and the flanges 119 or 121 should be spaced a sufficient distance from block 47 to clear this block. The corners of the cap 117 should be rounded (see FIG. 1).

The Connecting Assembly (FIG. 4) includes in addition to rod 39, which moves the Clamping Assembly as the cylinder 13 is moved, and pivot arm 99, a cam 131 pivotal about pin 59 by a linkage connected to piston rod 31. The linkage includes a lever 133 pivotal about a pin 135 near the end of rod 31 and a lever 137 pivoted about a pin 139 near the end of lever 133. The cam surface 141 (FIG. 2) of cam 131 is in actuating engagement with an intermediate section 143 of pin 101 and the pin 161 thus serves as follower carrying the Skid Assembly with it. Pivot arm 99 is not connected to cam 131 but carries a pin 145 which extends into a slot 147 (-FIG. 2) in the cam center. This pin slot combination serves to reset the pivot arm after an operation.

With the apparatus in the fully disengaged position (FIG. 2) movement of the piston 33 outwardly (to the left in FIG. 4) pivots cam 131. Since pivot arm 99 is not connected to cam 131, the cam alone moves initially. The cam surface 141 guides follower 143 inwardly towards block 47 until the cap holder 109 engages the work W. At this point the further out-ward movement of the piston causes the cam 131 to push the follower 143, the Skid Assembly and the pivot arm 99 around the curved portion 55 of the Anvil bending the work W.

In the use of the apparatus the piston 33 and cylinder 13 are set in the retracted position. (FIGS. 34.) The apparatus is properly placed with respect to the transformer and the transformer terminals W are aligned along the straight portion 51 of the block 47. Fluid is then supplied to fitting 25. This causes the piston 33 and the cylinder 13 to move relative to each other, the movement of the cylinder predominating. The cylinder moves away from the Anvil (right FIG. 4) pulling rod 39 and the Clamping Assembly and clamping the work W with the work between flange 89 and flange '57 Where it is positioned as shown in FIG. 1. (Note that plug 19 is outside of sleeve 11.)

The clamping of the work W prevents further movement of the cylinder 13. Only the piston 33 now moves towards the Anvil initially moving the Skid Assembly to engage the work and then moving the Skid Assembly around curvilinear portion 55 to bend the work. The end of slot 147 initially engaged by pin 145 is now removed from the pin.

The fluid valves (not shown) connected to fitting 25 may now be set to return or exhaust the fluid under piston 33 and fluid may be supplied to valve 37. This causes the piston 33 and cylinder 13 to be reset. The slot 147 is curved to engage pin 145 and to reset pivot arm 99.

The Clamping and Skid Assemblies may be set to bend bands or strips of a range of dimensions. Beyond this range caps 83 and 117 and blocks 77 and 109 of difierent dimensions or different form may be used. In the practice of this invention four sets of caps and blocks have been used to bend strips as follows over the following ranges.

While a preferred embodiment has been disclosed herein many modifications thereof are feasible. This invention then is not to be restricted except insofar as is necessitated by the spirit of the prior art.

I claim as my invention:

1. Bending apparatus for bending work comprising work holding means, work bending means, a cylinder, a piston slidable within said cylinder, means mounting said cylinder floating mechanically, a connection between said piston and one of said Work means, a connection between said cylinder and the other said work means, and means connected to said cylinder for supplying fluid to said cylinder in actuating relationship to said piston thereby to urge both said work holding means into holding engagement with said work and said Work bending means in bending engagement with said Work.

2. Bending apparatus for bending work comprising work holding means, work bending means, a cylinder, a piston slidable within said cylinder, means mounting said cylinder floating mechanically, a connection between said piston and one of said work means, a connection between said cylinder and the other said work means, the one of said connections including work bending means permitting pivotal movement of said bending means, and means connected to said cylinder for supplying fluid to said cylinder in actuating relationship to said piston thereby to urge both said work holding means into holding engagement with said work and said work bending means in bending engagement with said work.

3. Bending apparatus for bending Work including an anvil, a holding die, a bending die, a cylinder, a piston slidable within said cylinder, means mounting said cylinder floating mechanically, a connection between said cylinder and said holding die, a connection between said piston and said bending die, and means connected to said cylinder to supply fluid to said cylinder in actuating relationship to said piston thereby to actuate said holding die into holding relationship with said work and said bending die in bending relationship with said Work.

4. Bending apparatus for bending work comprising work holding means, Work bending means, a cylinder, a piston slidable within said cylinder, means mounting said cylinder floating mechanically, a connection between said piston and one of said work means, a connection between said cylinder and the other said work means, the one of said connections including said work bending means including linkage means permitting pivotal movement of said bending means and cam means for guiding said pivotal movement, and means connected to said cylinder for supplying fluid to said cylinder in actuating relationship to said piston thereby to urge both said work holding means into holding engagement with said work and said work bending means in bending engagement with said work.

5. Bending apparatus for bending work including an anvil, a holding die, a bending die, a cylinder, a piston slidable Within said cylinder, means mounting said cylinder floating mechanically, a connection between said cylinder and said holding die, a connection between said piston and said bending die, said last-named connection including linkage means permitting pivotal movement of said bending die and cam means for guiding said pivotal movement, and means connected to said cylinder to supply fluid to said cylinder in actuating relationship to said piston thereby to actuate said holding die into holding relationship with said work and said bending die in bending relationship with said work.

6. Portable bending apparatus for bending work, particularly the terminals of a transformer, comprising an anvil on which said work is disposed, a holding die, a bending die, a handle supporting said anvil and dies and including therein a unitary drive, and connections between said drive and said holding and bending dies actuable on actuation of said drive to urge said holding die into holding engagement with said work and said anvil and said bending die in bending engagement with said work and said anvil.

7. Portable bending apparatus for bending work comprising holding means, bending means, a hollow handle for said holding and bending means, a drive supported within said handle, and connections between said drive and said bending means and said holding means for actuating said holding means to hold said work and said bending means to bend said Work.

8. Portable bending apparatus for bending work comprising holding means, bending means, a handle for said holding and bending means, a unitary drive movably supported Within said handle, and connections between said drive and said bending means and said holding means for actuating said holding means to hold said work and said bending means to bend said work.

9. Work clamping apparatus for bending apparatus for bending bands, a plurality of said bands being arranged for bending with their elongated surfaces coplanar or with their elongated surfaces superimposed, the said clamping apparatus including an anvil having a flange, a holding assembly for holding said bands on said flange including a cap having at least one flange disposed with said last-named flange generally parallel to said flange of said anvil, said assembly also including mounting means for positioning said cap with said bands engaged between said flange of said cap and said flange of said anvil, said mounting means including means for adjusting the distance between said flange of said cap and said flange of said anvil to accommodate said plurality of bands, and means connected to said assembly for setting said assembly to hold said plurality of bands for bending between said anvil and said assembly with said bands between said flanges in engagement with said flanges.

10. Work clamping apparatus for bending apparatus for bending bands, a plurality of said bands being arranged for bending either in a first position with their elongated surfaces coplanar or in a second position with their elongated surfaces superimposed, the said clamping apparatus including an anvil having a flange, a holding assembly having a cap having a first flange and a second flange, and also having supporting means for said cap connected to said assembly including means for selectively setting said assembly to hold a plurality of bands in engagement with said anvil for bending, with said bands between said first flange and said flange of said anvil if said bands are in said first position and with said bands between said second flange and said flange of said anvil if said bands are in said second position, said first flange having a width such as to extend over the surfaces of all bands in said first position when said assembly is set for holding bands in said first position and said second flange having a width such as to extend only over one band when said assembly is set for holding bands in said second position.

11. Bending apparatus for bending work comprising work holding means movable in a predetermined direction into holding relationship with said work, work bending means movable generally in the opposite direction into bending relationship with said work, a fluid cylinder, a piston slidable within said cylinder and actuable by fluid to slide relative to said cylinder, means mounting said cylinder floating mechanically so that on the supply of fluid said cylinder and piston are both movable in opposite directions to the extent that each is not locked against movement, means connecting the cylinder member of the cylinder-piston combination to one of said work means, means connecting the piston member of said combination to said other work means, and means connected to said cylinder for supply fluid to said cylinder first to urge said work-holding means into holding engagement with said work and to lock the member of said combination connected to said holding means against movement and thereafter to cause said other member of said combination to actuate said work-bending means to bend said work.

12. Portable bending apparatus for bending work comprising holding means, bending means, a hollow handle for said holding and bending means, a fluid operable drive supported within said handle, said drive including a cylinder and a fluid operatable piston within said cylinder, said piston being movable within said cylinder and said cylinder floating within said handle so that both said cylinder and piston are movable within said handle, connections between one of said cylinder and piston and said holding means to hold said work, and connection between the other of said cylinder and piston to bend said work, the reaction between said work, said holding means, and said one of said cylinder and piston, preventing movement of said one as said other of said cylinder and piston moves to bend said work.

13. Bending apparatus for bending work having a surface of extending area generally perpendicular to the direction along which the bending force is applied, the said bending apparatus comprising an anvil having separate but coextensive holding and bending surfaces adapted to engage said work over said surface, said work to be held against said holding surface and to be bent about said bending surface, holding and bending die means cooperative with said holding and bending surfaces to hold and bend said work respectively, a unitary drive, and connections between said drive and said holding die means and connections between said drive and said bending die means actuable in sequence on actuation of said drive to urge said holding die means sequentially first into holding engagement with said work and said holding surface and then, responsive to the holding engagement of said holding die means and said work, to urge said bending die means into bending engagement with said work and said bending surface.

References Cited in the file of this patent UNITED STATES PATENTS 1,493,325 Donaldson May 6, 1924 2,175,679 Beatty Oct. 10, 1939 2,438,057 Kilham Mar. 16, 1948 2,476,595 Green July 19, 1949 2,476,596 Green July 19, 1949 2,482,617 Green Sept. 20, 1949 2,745,385 Shuff May 15, 1956 2,866,493 Kovalcik Dec. 30, 1958 2,892,479 Holsclaw June 30, 1959 2,915,106 Green Dec. 1, '1959 3,021,738 Anderson et a1 Feb. 20, 1962 

1. BENDING APPARATUS FOR BENDING WORK COMPRISING WORK HOLDING MEANS, WORK BENDING MEANS, A CYLINDER, A PISTON SLIDABLE WITHIN SAID CYLINDER, MEANS MOUNTING SAID CYLINDER FLOATING MECHANICALLY, A CONNECTION BETWEEN SAID PISTON AND ONE OF SAID WORK MEANS, A CONNECTION BETWEEN SAID CYLINDER AND THE OTHER SAID WORK MEANS, AND MEANS CONNECTED TO SAID CYLINDER FOR SUPPLYING FLUID TO SAID CYLINDER IN ACTUATING RELATIONSHIP TO SAID PISTON THEREBY TO URGE BOTH SAID WORK HOLDING MEANS INTO HOLDING ENGAGEMENT WITH SAID WORK AND SAID WORK BENDING MEANS IN BENDING ENGAGEMENT WITH SAID WORK. 